Piston vibratory pump

ABSTRACT

A vibratory pump for dispensing a fluid in a highly controllable manner includes a pumping mechanism in which a piston is slidably disposed within a chamber having an inlet and an outlet spaced from one another. The piston is shaped similarly to the interior of the chamber and is capable of moving within the chamber in a manner that prevents any fluid in the chamber from flowing between the chamber and the piston. As a result, the pumping mechanism does not require the use of any separate compressible or elastic sealing members, thereby increasing the reliability and useful life of the pump.

FIELD OF THE INVENTION

The present invention related to vibrating pumps in general, and more specifically to vibrating pumps including a piston as the vibrating member.

BACKGROUND OF THE INVENTION

Vibratory pumps are often used for dispensing selected amounts of a liquid from a reservoir of the liquid to a desired location. These pumps have various uses because of their ability to meter very precisely the amounts of fluid dispensed from the pumps, and to quickly change the dispensed amounts in response to changes in the vibratory frequency of the pumps. Therefore, these types of vibratory pumps are highly useful in a wide variety of applications.

In prior art vibratory pumps, such as those disclosed in U.S. Pat. Nos. 6,315,533; 6,364,622; 6,428,289; and 6,604,920 which are commonly owned with this application and incorporated herein by reference, the vibratory pumps utilize a motor to selectively open and close a chamber that is used to pump the fluid. As the chamber is opened, the fluid enters the chamber due to a vacuum created in the chamber by the opening of the chamber. When the chamber is closed, due to the shape or components used to form the chamber, the fluid is urged out of the chamber to dispense the liquid from the pump.

However, in these types of pumps, the pump requires one or more sealing members within the pump to prevent the fluid to be dispensed from flowing other than in the desired direction, and thereby limiting the effectiveness of the pump. With regard to theses types of sealing members, they are formed of material that have a certain amount of elasticity or compressibility to provide an effective seal. However, due to this property of the sealing members, over time, the sealing members can degrade, especially in the presence of certain types of fluids, such that the fluid seal becomes less effective, and ultimately fails. At this point, the sealing member needs to be replaced or, due to the severity of the failure, the pump may be damaged beyond repair.

Therefore, it is desirable to develop a vibratory pump having a construction that does not include any compressible or elastic sealing members that can potentially fail and/or be negatively affected by the type of fluid being dispensed through the pump.

SUMMARY OF THE INVENTION

According to a primary aspect of the present invention, the vibratory pump is formed with a chamber having an inlet extending into the chamber, and outlet extending out of the chamber and spaced from the inlet. The chamber also includes a shaft collar located opposite the outlet for the chamber and through which a shaft slidably extends. The shaft is connected at one end to a vibratory mechanism, and is connected at the other end within the chamber to a piston. The piston has a shape which closely conforms the shape of the chamber, such that due to the operation of the vibrating mechanism, the piston can slidably oscillate within the chamber. The oscillation of the piston within the chamber causes a slight vacuum to be created in the chamber as the chamber moves in a first direction past the inlet, consequently drawing fluid into the chamber through the inlet for the chamber. Movement of the piston in the opposite direction then closes the inlet and urges the fluid drawn into the chamber through the outlet of the chamber as the piston moves through the chamber towards the outlet. The size of the piston conforms closely to interior shape of the chamber such that the piston does not allow any fluid to flow between the piston and the chamber. Also, the piston and the chamber are formed of materials that are self-lubricating to enable them to move freely with respect to one another, and that are highly resistant to any damaging or corrosive properties of the fluids being dispensed by the pump such that the piston and chamber can be utilized to dispense a wide variety of fluids.

According to another aspect of the present invention, the chamber can include multiple inlets in order to increase the amount of fluid being drawn into the chamber during the operation of the pump. Also, the outlet for the chamber can be disposed in a nozzle secured to the chamber to enable the pattern or amount of fluid being dispensed from the chamber to be varied as desired.

According to still another aspect of the present invention, the chamber and piston contained within the chamber can be formed as an attachment that is attachable to an existing vibratory motor or similar device in order to enable the device to be converted to a piston pumping device.

Numerous additional advantages, aspects and features of the present invention will be made apparent from the following detailed description taken together with the drawing figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the best mode currently contemplated of practicing the present invention.

In the drawings:

FIG. 1 is a cross-sectional view of the vibratory piston pumping mechanism of the present invention; and

FIG. 2 is a cross-sectional view of an alternative embodiment of the mechanism of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

With reference now to the drawing figures in which like reference numerals designate like parts throughout the disclosure, a pump constructed according present invention is indicated generally at 100 in FIG. 1. The pump 100 includes a casing 1 that can be formed of any suitable rigid and liquid-impervious material. The casing 1 encloses a motor 3 that is secured to the interior of the casing 1. The motor 3 is in turn connected via a shaft 2 to a rotating member 4 that is rotated in response to the rotation of the shaft 2 by the motor 3. The power for the motor 3 is supplied by a pair of batteries 20 positioned within receptacles 21 located within the casing 1 in preferred embodiment. Alternatively, the motor 3 may also be powered by other suitable means, such as a plug (not shown) connected to the motor 3 at one end and insertable into an electrical outlet at the opposite end, among others.

The rotating member 4 is connected via an extension 5 and connectors 105 to a bracket 6 disposed at one end of a piston rod 7. The bracket 6 includes a pivot pin 8 to which the extension 5 is connected in order to enable the bracket 6 to rotate with respect to the extension 5 when the rotating member 4 and motor 3 are operating. The piston shaft 7 extends through a shaft opening 8 into a chamber 9. The shaft opening 8 is located within a shaft collar 108 that can be formed integrally as part of the chamber 9 or as a separate part that is subsequently fixedly attached to the chamber 9. The chamber 9, and preferably the shaft collar 8, is formed from a generally rigid material that is highly resistant to any harsh fluids that may potentially be dispersed by the pump, such as a hard plastic, and defines an interior 10 that is in fluid communication with a pair of inlets 11 and an outlet 12. The inlets 11 can be integrally formed with the chamber 9, or can be formed separately from the chamber 9 of a material similar to the chamber 9, as desired. Each inlet 11 is attached to a tube 13 formed of a rigid or flexible material which extends outwardly from the inlet 11 and out of the casing 1 through a collar 117 located on the casing 1. The collar 117 is releasably engaged, and preferably threadedly engaged, with a bottle 18 having any desired configuration. The tubes 13 extend into the bottle 18 to approximately the bottom of the bottle 18, such that the tubes 13 are normally always positioned beneath the level of a fluid or liquid 19 disposed within the bottle 18.

The outlet 12 of the chamber 9 can be formed integrally with the casing 9, but preferably is formed within a nozzle 112 that can have any desired configuration for dispensing the fluid 19 out of the casing 1 in a desired manner, such as by incorporating a number of different outlets 12 each in fluid communication with the interior 10 of the chamber 9. However, in a particularly preferred embodiment, the outlet 12 includes an inner portion 15 that has a tapering cross section as the inner portion extends away from the chamber interior 10, and an outer portion 16 that has a generally circular cross section. Thus, fluid directed out of the chamber 9 is collected in the inner section 15 and compressed as it moves to the outer section 16 such that a pressurized stream of the fluid 19 is dispensed out of the outlet 12. The nozzle 112, similarly to the shaft collar 108, is formed of a highly damage-resistant material that can be integrally or separately formed from the chamber 9.

The fluid 19 is moved through the outlet 12 in the nozzle 112 by the oscillating movement of a piston 17 attached to the piston shaft 7 opposite the bracket 6. The piston 17 has a cross-sectional shape corresponding to the shape of the interior 10 defined within the chamber 9 such that the movement of the piston 17 effectively pushes any fluid 19 located within the interior 10 of the chamber 9 between the piston 17 and the nozzle 112 out through the outlet 12. Preferably, the chamber 9 has a generally circular cross-section with the piston 17 also having a generally circular cross-section with a diameter slightly less than that of the chamber interior 10. The difference in the diameter between the chamber interior 10 and the piston 17 is small, i.e., small enough to prevent any significant amount of fluid from flowing between the piston 17 and the chamber 9. Thus, while the piston 17 can move freely within the chamber interior 10, the tight tolerances between the piston 17 and the chamber interior 10, effectively prevent any significant amount of fluid 19 from flowing between the piston 17 and the chamber 9. The ability of the piston 17 to move freely within the chamber 9 with these tight tolerances can be assisted by forming the piston 17 and or the chamber 9, or by applying a coating 120 to the chamber interior 10 with a self-lubricating material that enables the piston 17 to slide more easily along the chamber interior 10. Different types of material that are suitable for this purpose include various plastics, plastic-rubber composites, and synthetic rubbers such as alkyds, polyurethanes, silicones, polyacrylics, and fluoropolymer resins, such as Teflon®, among other suitable materials.

In operation, after the casing 1 is effectively attached to the bottle 18 utilizing the collar 117, a switch 21 disposed on the casing 1 is activated which supplies power from the batteries 20 to the motor 3. The operation of the motor 3 results in a rotation of the shaft 2 and the rotatable member 4, consequently causing the shaft 7 and piston 17 to oscillate with respect to the chamber 9. As the piston 17 is drawn by the shaft 7 away from the outlet 12, the movement of the piston 17 creates a vacuum within the chamber interior 10, thereby drawing liquid 19 from within the bottle 18 through the tubes 13 and into the chamber 9 through the inlets 11. When the piston 17 begins moving forwardly through the chamber 9 towards the outlet 12, the piston 17 pushes all of the fluid 19 drawn into the chamber 9 and positioned between the piston 17 and the outlet 12 towards the outlet 12, consequently dispensing the fluid 19 through the outlet 12 in the desired manner. Due to the tight tolerance between the piston 17 and the chamber 9, the fluid 19 does not pass between the piston 17 and the chamber 9 as the piston 17 moves towards the outlet to ensure the fluid is dispensed from within the chamber 9. After the piston 17 contacts the nozzle 112, the piston 17 then is withdrawn or moved away from the outlet 12 by the further rotation of the rotatable member 4 to move or draw more fluid 19 into the chamber 9 through the inlets 11 in order to repeat the cycle.

In a preferred embodiment, to vary the volume of fluid 19 dispensed by the pump 100, the motor 3 can be operated to cause the piston 17 to oscillate within the chamber 9 with in a frequency range of between about 100 to 10,000 cycles per second. The various types of motors 3 which can be utilized in this invention are those which are capable of oscillating the piston 17 within the chamber 9 within this frequency range, including electric motors, piezoelectric motors and other suitable types of motors.

Referring now to FIG. 2, in an alternative embodiment for the pump 100, the chamber 9 can be positioned concentrically within a secondary chamber or enclosure 24. The enclosure 24 forms a space 26 around the chamber 9 and includes an inlet tube 28 extending outwardly from and preferably integrally formed with the enclosure 24. Also, the chamber 9 is formed with a number of inlets 11′ which are formed as openings or bores extending through the exterior of the chamber 9. The operation of this embodiment is highly similar to the embodiment in FIG. 1 because the fluid 19 is drawn upwardly through the inlet tube 28 into the enclosure 24 and through the openings 11′ into the chamber 9 for direction through the outlet 12 by the oscillating piston 17. However, due to the construction of this embodiment without an outer casing 1, the chamber 9 can be utilized as an attachment for an existing oscillating mechanism (not shown) to which the shaft 7 and piston 17 can be releasably attached in order to enable the mechanism to function as a pump 100.

Various alternatives are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention. 

1. A vibratory pump comprising: a) a pump chamber defining an interior space and including a fluid inlet and a fluid outlet spaced from the fluid inlet; b) a piston having a unitary construction, and disposed within the interior space of and sealingly engaged with the chamber; c) a shaft connected to the piston and extending outwardly from the chamber; d) an enclosure sealingly secured around and in fluid communication with the fluid inlet of the pump chamber to define a fluid-tight space around the chamber and the fluid inlet, the enclosure including a fluid receiving aperture formed in the enclosure and spaced from the chamber and a fluid inlet tube having one end connected to the enclosure around the aperture and the opposite end adapted to be positioned within a supply of fluid to be pumped; and e) a vibratory mechanism connected to the shaft to oscillate the shaft and piston within the chamber, wherein the pump does not include a separate sealing to prevent the leaking of fluid between the piston and chamber.
 2. The pump of claim 1, wherein the chamber includes a pair of inlets spaced from the outlet, and the enclosure is positioned around both of the pair of inlets.
 3. The pump of claim 1, wherein the outlet includes a wide inner portion adjacent the interior space of the chamber in a narrow outer portion.
 4. The pump of claim 1, wherein the fluid outlet is releasably secured to the chamber.
 5. The pump of claim 4, wherein the fluid outlet is formed as a nozzle threadedly engaged with the chamber.
 6. The pump of claim 1, wherein the vibratory mechanism is an electric motor.
 7. The pump of claim 1, wherein the piston is formed of a self-lubricating material.
 8. The pump of claim 7, wherein the piston is formed from a plastic.
 9. The pump of claim 1 wherein the enclosure includes a body disposed around and spaced from the chamber within which the fluid receiving aperture is formed, and a pair of opposed end plates having openings therein through which the chamber extends, the end plates affixed to the chamber around the entire opening therein in a fluid-tight manner.
 10. (canceled)
 11. The pump of claim 1, wherein the fluid inlet is formed as a bore extending through the chamber.
 12. The pump of claim 1 further comprising a shaft collar secured to the chamber opposite the fluid outlet.
 13. The pump of claim 1, wherein the chamber is formed of a plastic.
 14. (canceled)
 15. (canceled)
 16. (canceled)
 17. The pump of claim 1 wherein the piston is coated with a lubricating material.
 18. The pump of claim 1 wherein the chamber is coated with a lubricating material.
 19. (canceled)
 20. A vibratory pump consisting of: a) a pump chamber defining an interior space and including a fluid inlet and a fluid outlet spaced from the fluid inlet; b) a piston consisting of a unitary piece of a rigid and self-lubricating hard plastic material disposed within the interior space of and sealingly engaged with the chamber; c) a shaft connected to the piston and extending outwardly from the chamber; d) an enclosure sealingly secured to the chamber around the fluid inlet of the pump chamber to define a fluid-tight space around the chamber and the fluid inlet, the enclosure including a body disposed around and spaced from the chamber, the chamber extending through opposed ends of the body, a fluid receiving aperture formed in the enclosure and spaced from the chamber and a fluid inlet tube having one end connected to the enclosure around the aperture and the opposite end adapted to be positioned within a supply of fluid to be pumped; and e) a vibratory mechanism connected to the shaft to oscillate the shaft and piston within the chamber.
 21. A vibratory pump consisting of: a) a pump chamber defining an interior space and including a fluid inlet and a fluid outlet spaced from the fluid inlet; b) a piston consisting of a unitary piece of a rigid and self-lubricating hard plastic material disposed within the interior space of and sealingly engaged with the chamber; c) a shaft connected to the piston and extending outwardly from the chamber; d) an enclosure sealingly secured directly to the pump chamber around the fluid inlet of the pump chamber to define a fluid-tight space around the chamber and the fluid inlet, the enclosure including a body having a side wall disposed around and spaced from the chamber and a pair of opposed end walls connected between the side wall and the chamber, the chamber extending through opposed ends of the body, a fluid receiving aperture formed in the enclosure and spaced from the chamber and a fluid inlet tube having one end connected to the enclosure around the aperture and the opposite end adapted to be positioned within a supply of fluid to be pumped, the fluid-tight space configured to receive fluid from the fluid inlet tube and to direct the fluid through the space around the chamber to the fluid inlet in the chamber; and e) a vibratory mechanism connected to the shaft to oscillate the shaft and piston within the chamber. 